I have had a couple of people ask for the link to my article but the restrictions here will not allow me to posts links or reply to PMs till I have 15 posts. So if you are interested just google project boat zen and you will find it. Sorry about that but best I can do. And to the mods i really am not here to spam but as I run a board too I completely understand. I'm just here to help when i can.

The lower forward shroud chain plate always has some rust staining on the deck so wanted to take a look.

Here are pics what I found. Seems to be a stress corrosion crack at the rusty area. The crack occurs where the chain plate has a sligth bend for alingment to the wire (shop made bend). This chain plate is about 6 years old and has about 30,000 miles on it.

One of the attached pics has another chain plate next to the existing (this was taken after I polished the existing plate some to clean it up). This old chain plate with no wire attached was on the boat when I bought her (in storage). You can see some corrosion, and there is a small crack running width of the chain plate. There is an indentation near the crack- indent was made when bend was done by shop, probaly while on the break machine. Seems both crevice corrosion and stress corriosion happened on the old chain plate that was stored on the boat. All the corrosion is occuring in the deck penetration area (where water could collect).

Looks like that is a copper tube spec. Have not looked at complete spec but probably cannot get in bar form (only tube) and probably does not have the needed strength. The only copper alloy I know of for chain plates would be bronze (best is silicon bronze).

Looks like that is a copper tube spec. Have not looked at complete spec but probably cannot get in bar form (only tube) and probably does not have the needed strength. The only copper alloy I know of for chain plates would be bronze (best is silicon bronze).

Thanks for the fast come-back.
I asked about that alloy as I remember it from a few decades ago being touted by (Bruce Roberts?) a build it yourself boat plans outfit as a no coating needed corrosion free replacement for steel in building a boat, I could easily be mis-remembering the metal specified but if I got it right then it must have been avail. in plate form, at least in AU.

Thanks for the fast come-back.
I asked about that alloy as I remember it from a few decades ago being touted by (Bruce Roberts?) a build it yourself boat plans outfit as a no coating needed corrosion free replacement for steel in building a boat, I could easily be mis-remembering the metal specified but if I got it right then it must have been avail. in plate form, at least in AU.

Looks like you can get plate, but costs would be a lot. This material is copper/ nickel both very expensive materials. Note the company that sells it refers to it as a bronze. Similar to bronze but the nickel would raise the cost.

The C76200 is a VERY heat temper dependent metal, with yield strengths ranging from 21,000psi to 110,000psi. This makes is non-suitable for use as a structual metal, unless a huge amount of engineering is done. The upside is that the lower limit is similar to aluminium, so you could borrow a lot from aluminium design. But the price premium would be huge.

I'd go with titanium, but I would avoid AlliedTitanium. I went with them and placed an order which took a month for them to tell me was not started. Since I had to remove them to measure, I was stuck unable to sail on their word they would be done in 15days. Bleh!

I ended up finding a local place that will have them to me in two days.

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